Reinforcer efficacy of grain for horses

Abstract

Positive reinforcement is becoming more common in horse training. Identifying effective reinforcers is critical for training success. The aim of this study was to determine relative reinforcer efficacy of different grains. Four horses learned to muzzle touch a target, after which they were tested using a progressive ratio schedule of reinforcement with different grains as the consequence. Break points were used to determine relative reinforcer efficacy of each grain and were also converted into unit price per kilocalorie to determine if caloric value impacted reinforcer efficacy. Condition 1 compared three textured grains that spanned industry-accepted standards of low to high nonstructural carbohydrate content. Condition 2 compared three pelleted grains that similarly differed in nonstructural carbohydrate content, comparable to Condition 1, but that had a different texture than those of Condition 1. Finally, Condition 3 directly compared one grain each from Conditions 1 and 2. Results showed overall little difference in reinforcer efficacy or unit price between grains but found that all grains tested functioned as reinforcers for the horses. This suggests that a range of commercially available grains can maintain behavior and therefore be used for training. We also identified possible extraexperimental factors that impact reinforcer efficacy.

Moving toward Fear-Free Husbandry and Veterinary Care for Horses

“…Positive reinforcement-based training is less common in the horse industry than in many training sectors, but has experienced a dramatic rise in popularity in recent years [ 47 , 94 ]. One of the significant benefits of positive reinforcement is that it has the potential to improve the horse’s feelings about humans and provides positive HAIs [ 95 , 96 , 97 , 98 ].…”

“…Nonetheless, evidence from a wide range of other species including prey species and ungulates would suggest that this approach would be highly effective in horses, and anecdotally, it is already routine practice for some horse trainers and behaviour professionals [ 115 ]. The reinforcer is typically food, however, tactile stimulation such as wither scratching has also been used [ 57 , 94 , 116 , 117 , 118 ]. Studies comparing horse preferences between food and human contact indicate food is preferable in most instances, regardless of the horse’s previous training history [ 116 , 117 ], but tactile contact may be a more appropriate reinforcer in some circumstances, such as when working with foals [ 118 ].…”